Open Access
Add to BibSonomyAbstract
We correct a table showing the signal-to-noise ratio obtained in coherent detection. We also clarify a table showing the bandwidth requirements for homodyne and heterodyne downconverters. Otherwise, our previous results and conclusions are unchanged.
©2008 Optical Society of America
In Section 3 of article [1], we showed a table of the signal-to-noise ratios (SNR) per symbol γ s obtained when using coherent detection in conjunction with different optoelectronic downconverters under different noise regimes. We found an error for single-quadrature homodyne downconversion in the shot-noise-limited case. The corrected table is given in Table 1.
Table 1. SNR per symbol for various receiver configurations. For the ASE-limited cases, n̄s is the average number of photons received per symbol, NA is the number of fiber spans, and nsp is the spontaneous emission noise factor of the inline amplifiers. For the LO shot-noise-limited cases, n̄r=ηn̄s is the number of detected photons per symbol, where η is the quantum efficiency of the photodiodes. For the ASE-limited heterodyne case, image-band rejection is assumed.
In addition, we wish to clarify the bandwidth requirement for a heterodyne downconverter by making the following modification to Table 2.
Table 2. Comparison between homodyne and heterodyne downconverters.